The process in agriculture of cultivating plants and causing them to bloom and/or bear fruit directly affects the yield and is important for determining economical value. In crops, fruits, vegetables and decorative flowering plants, products are formed after flowering so that the flowering period determines the period for yielding and/or shipment. Accordingly, a technique for regulating the flowering of plants in an inexpensive way makes a planned agricultural production possible and brings about an innovation in agriculture. The present invention is directed to flower-inducing substances for carrying out the foregoing concept which can be widely utilized in general and to methods for producing the flower-inducing substances.
In many cases, plants change their mode of growth from vegetative growth to reproductive growth, depending upon daily periodicity, and form flower buds on meristematic tissue and finally bloom. A group of plants which flower when daytime becomes long and nighttime becomes short are called long-day plants and a group of plants which bloom when daytime becomes short and nighttime becomes long are called short-day plants. Cabbage and spinach are long-day plants and chrysanthemum, morning glory, strawberry, rice plants, wheat, etc. are short-day plants. In addition, there are plants which induce flower buds in response to temperature. Dendrobium, which is one species of orchid, is a typical plant which induces flower buds at a low temperature. In order to induce flower buds on cabbage or spinach, a low temperature is required, in addition to long days.
As stated above, plants form flowers and bloom depending upon environmental conditions inherent to their species. However, it is considered that a substance for inducing the reaction of forming flower buds would be common to any plants. Where plants are put under environmental conditions which are inherent to the respective plants but in which flowering is induced, a common substance is synthesized, acts on the meristematic tissue and induces flower buds there.